A network video surveillance service is a broadband-based value-added service for surveilling, transmitting, storing, and managing remote images. The network video surveillance service uses a broadband network to connect scattered and independent image collection points to implement cross-region and unified surveillance, storage, management, and resource sharing within all coverage.
To further assist in surveillance decision making, a data collector may be connected to a peripheral unit to collect data of an environment near a surveillance site. The data collector may be a temperature and humidity collector, a wind direction and wind speed collector, a noise collector, or the like. The collected data may be used for a subsequent query and analysis or may be directly called during surveillance.
When a user calls a surveillance video, some surveillance devices directly superimpose data collected by the peripheral unit on video data (that is, video streams) during coding at a source and play the superimposed data for a surveillance person. In this manner of superimposing data at the source, everybody has to see the data. However, not everybody needs to see the collected data. This manner of playing the surveillance video is not flexible.